diff --git a/jpm b/jpm
index f30a84f6..d03844b9 100755
--- a/jpm
+++ b/jpm
@@ -132,6 +132,15 @@
   "Convert url with potential bad characters into a file path element."
   (peg/compile ~(% (any (+ (/ '(set "<>:\"/\\|?*") "_") '1)))))
 
+(def- entry-replacer
+  "Convert url with potential bad characters into an entry-name"
+  (peg/compile ~(% (any (+ '(range "AZ" "az" "09" "__") (/ '1 ,|(string "_" ($ 0) "_")))))))
+
+(defn entry-replace
+  "Escape special characters in the entry-name"
+  [name]
+  (get (peg/match entry-replacer name) 0))
+
 (defn filepath-replace
   "Remove special characters from a string or path
   to make it into a path segment."
@@ -440,14 +449,14 @@
 (defn- entry-name
   "Name of symbol that enters static compilation of a module."
   [name]
-  (string "janet_module_entry_" (filepath-replace name)))
+  (string "janet_module_entry_" (entry-replace name)))
 
 (defn- compile-c
   "Compile a C file into an object file."
   [opts src dest &opt static?]
   (def cc (opt opts :compiler default-compiler))
   (def cflags [;(getcflags opts) ;(if static? [] dynamic-cflags)])
-  (def entry-defines (if-let [n (opts :entry-name)]
+  (def entry-defines (if-let [n (and static? (opts :entry-name))]
                        [(make-define "JANET_ENTRY_NAME" n)]
                        []))
   (def defines [;(make-defines (opt opts :defines {})) ;entry-defines])
@@ -465,7 +474,7 @@
   [opts src dest &opt static?]
   (def cpp (opt opts :cpp-compiler default-cpp-compiler))
   (def cflags [;(getcppflags opts) ;(if static? [] dynamic-cflags)])
-  (def entry-defines (if-let [n (opts :entry-name)]
+  (def entry-defines (if-let [n (and static? (opts :entry-name))]
                        [(make-define "JANET_ENTRY_NAME" n)]
                        []))
   (def defines [;(make-defines (opt opts :defines {})) ;entry-defines])
diff --git a/test/install/project.janet b/test/install/project.janet
index 916abfda..5f3ce572 100644
--- a/test/install/project.janet
+++ b/test/install/project.janet
@@ -13,6 +13,10 @@
     :name "testmod3"
     :source @["testmod3.cpp"])
 
+(declare-native
+    :name "test-mod-4"
+    :source @["testmod4.c"])
+
 (declare-executable
   :name "testexec"
   :entry "testexec.janet")
diff --git a/test/install/testexec.janet b/test/install/testexec.janet
index 045a6e4e..4f4c5020 100644
--- a/test/install/testexec.janet
+++ b/test/install/testexec.janet
@@ -1,7 +1,8 @@
 (use build/testmod)
 (use build/testmod2)
 (use build/testmod3)
+(use build/test-mod-4)
 
 (defn main [&]
   (print "Hello from executable!")
-  (print (+ (get5) (get6) (get7))))
+  (print (+ (get5) (get6) (get7) (get8))))
diff --git a/test/install/testmod4.c b/test/install/testmod4.c
new file mode 100644
index 00000000..b29249dd
--- /dev/null
+++ b/test/install/testmod4.c
@@ -0,0 +1,40 @@
+/*
+* Copyright (c) 2020 Calvin Rose and contributors
+*
+* Permission is hereby granted, free of charge, to any person obtaining a copy
+* of this software and associated documentation files (the "Software"), to
+* deal in the Software without restriction, including without limitation the
+* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+* sell copies of the Software, and to permit persons to whom the Software is
+* furnished to do so, subject to the following conditions:
+*
+* The above copyright notice and this permission notice shall be included in
+* all copies or substantial portions of the Software.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+* IN THE SOFTWARE.
+*/
+
+/* A very simple native module */
+
+#include <janet.h>
+
+static Janet cfun_get_eight(int32_t argc, Janet *argv) {
+    (void) argv;
+    janet_fixarity(argc, 0);
+    return janet_wrap_number(8.0);
+}
+
+static const JanetReg array_cfuns[] = {
+    {"get8", cfun_get_eight, NULL},
+    {NULL, NULL, NULL}
+};
+
+JANET_MODULE_ENTRY(JanetTable *env) {
+    janet_cfuns(env, NULL, array_cfuns);
+}